1. Field of the Invention
The invention relates to a single lumen intra-aortic balloon catheter. More particularly, the invention relates to a single lumen intra-aortic balloon catheter designed for percutaneous insertion into the aorta of an infant.
2. Description of the Prior Art
Intra-aortic balloon pumping (IABP) is a recognized technique for cardiac assistance for a failing heart. It has become a standard mode of treatment for perioperative low cardiac output syndrome and cardiogenic shock after myocardial infarction in adults. Further, it has been used for such purposes as helping to wean an adult patient away from cardiopulmonary bypass, and to support a patient during a difficult postoperative period. Each year since 1968, the IABP has been used with increasing frequency on an estimated 100,000 adults. The only pediatric IAB catheter currently on the market is produced by Datascope Corp. The success of the Datascope pediatric IAB is reflected in several studies. See, for example, Intra-aortic balloon pumping in children by Webster and Veasy in Heart & Lung: The Journal of Critical Care (1985) and Intra-aortic balloon pumping in infants and children by Veasy, Blalock, Orth, and Boucek in Therapy and Prevention (1983). The major problem with the present state of the art pediatric catheter, however, is the fact that it must be inserted surgically. Due to design limitations imposed by the dimensions of an infant's femoral artery the pediatric IAB catheter is too small to accommodate a lumen for a guide wire.
A guide wire facilitates percutaneous insertion by guiding the catheter into the insertion site in the artery. When a guide wire is used it is generally inserted through a lumen in an angiographic needle and into the artery. After the needle is removed, the guide wire is already in the artery to guide the balloon into the artery.
The femoral artery has heretofore been used for insertion of the present state of the art balloon catheters because of the large diameter of that artery. However, due to the relatively large entering cross-section of the state of the art pediatric IAB catheter, and the relatively small pediatric femoral artery diameter, guide wire insertion through a guide wire in the catheter cannot be performed. Considerable and rather delicate surgery must be performed in order to reach and isolate the femoral artery in a manner which enables the balloons to be introduced. Surgical insertion of the IAB catheter generally takes as long as thirty minutes. In many cases, only vascular surgeons are willing or able to undertake this surgery, thus limiting the use of the otherwise advantageous pediatric IAB catheter. Furthermore, considerable difficulty is often encountered in the healing of these surgical incisions because of their location in the groin.
Currently, IABs for adults are non-surgically inserted through a sheath positioned in the femoral artery. Many attempts have been to minimize the size of the sheath so as to ease insertion of the sheath and to facilitate healing of the insertion site. Unfortunately, an infant's femoral artery is too small to accommodate a sheath large enough to be used with the pediatric IAB. Therefore, the need exists for a sheathless method for inserting a pediatric IAB.
Considering the complexity and the time consuming nature of a surgical IAB catheter insertion procedure and the fact that surgical incisions made in the groin area are difficult to heal, the need exists for a pediatric IAB catheter capable of being inserted percutaneously.
While the present state of the art pediatric IAB catheter may be suitable for the particular purpose employed, or for general use, it would not be as suitable for the purposes of the present invention as disclosed hereafter.